Californians celebrate Earth Day and the ecology movement over the past month, the state’s public schools are making steady progress in implementing some of the most comprehensive environmental education guidelines in the country, educators and environmentalists say.

Buoyed by $4 million in the current state budget for K-12 environmental education, teachers are planning field trips to mountains and beaches, creating lessons on ecosystems and watersheds and showing students how human activity affects the planet. In April, thousands of students turned out for Earth Day events, picking up trash, pulling weeds and planting trees.

“While many states are engaged in strategic efforts to implement environmental education K-12, California is certainly emerging as a leader,” said Sarah Bodor, director of policy and affiliate relations for the North American Association for Environmental Education. “We’re excited to watch as many diverse partners are coming together to ensure that all California students get access to rich, authentic learning that advances environmental literacy and civic engagement.”

In 2015, the State Department of Education published a 48-page plan, called the Blueprint for Environmental Literacy, charting how environmental education will be taught in almost every subject at every grade level. Fourth-graders, for example, when studying California history will also learn about invasive plants brought by the Spanish and how gold mining affected rivers. In science classes, high school students will learn about the changing chemistry of the oceans and how warming air is linked to extreme weather.

The blueprint itself has no timeline and is not mandatory, but environmental principles are part of the frameworks for health and history-social science and are a major component of the new Next Generation Science Standards. Testing on the new science standards begins next year.

State Superintendent of Public Instruction Tom Torlakson pushed for the environmental guidelines as a way to supplement and expand students’ outdoor education, which some schools have offered informally for years, and encourage future generations to protect the planet.

“The critical environmental concerns that face California demand that we think deeply about how to build a future that is sustainable, healthy, prosperous and equitable,” Torlakson wrote in the Blueprint for Environmental Literacy. “We must invest our very best thinking, our very best efforts and — above all — our very best people in improving the quality and reach of student education for environmental literacy in California.”

In the science standards, every grade level and nearly every unit includes lessons on how humans impact their environment. In kindergarten, for example, students learn how people make choices — such as littering — that affect the water, air and land. In middle school, students learn how energy is transferred in an ecosystem, such as in composting. In high school, students learn about the links between natural resources management, biological diversity and sustainable human societies.

In this year’s state budget, the Legislature allocated $4 million for the California Regional Environmental Education Community Network, a state Department of Education program that links schools with nonprofits and other state agencies to promote K-12 environmental science. Divided into 11 statewide regions, the network offers local information about grants for supplies and field trips, curriculum, field trip options, teacher training and classroom project ideas. The grants, many of which have rolling deadlines, vary depending on the size of the project. Grant-funded projects range from trees and seeds for school gardens, to class pets, to field trips to the ocean to learn about marine biology, coastal habitats and ocean acidification.

The $4 million will be used to promote the guidelines and help teachers implement them. Most of the grant money is from separate nonprofits or other government agencies. Teachers can apply for the grants directly.

Since California began its push for environmental education several years ago, a handful of counties and districts have taken the lead. The Santa Cruz and San Mateo county offices of education, for example, have each hired full-time environmental education specialists and educators in Riverside and San Bernardino counties have created a collaborative to give grants for field trips and supplies, share ideas and help teachers with environmental lesson plans, said Karen Cowe, executive officer of Ten Strands, a nonprofit devoted to California K-12 environmental education. The collaborative is funded by Riverside and San Bernardino county offices of education and local environmental and community nonprofits.

“There’s a lot of interest throughout the state and it’s been heartening,” she said. “But it’s a big lift to get these principles and concepts implemented. We look at it as a long game. Long but worthwhile.”

Plumas County has been among the bright spots, she said. Rob Wade, science and outdoor education coordinator for the Plumas County Office of Education, has been leading camping trips, hikes and environmental projects for the county’s K-12 students for 22 years.

When he started, the county’s outdoor education program consisted of a one-night camping trip for 6th-graders. Now that camping trip is a week-long and is a beloved rite of passage in the Northern California county, where students fundraise and look forward to the excursion all year round, he said.

The camping trip is now dubbed “From Plumas to the Pacific,” and allows students to see how water travels from the Plumas County mountains to the Pacific Ocean. Traveling by foot, raft and bus, students follow the Feather River from its backcountry headwaters, through the Feather River Canyon to the Oroville Dam, down the Sacramento Valley to the Delta and eventually to the Golden Gate. Along the way they visit a fish hatchery, a wildlife refuge, the confluence of the Sacramento and San Joaquin rivers, and the Bay Model in Sausalito. They learn about wetlands, irrigation, salmon, California history and ecology.

“We Lewis-and-Clark it. We just see where the river goes,” Wade said. “I’ve done this trip for so many years, but it never gets tiring because it’s always a different group of kids. It’s always new to them.”

In addition, Wade’s office has created partnerships with the Audubon Society, U.S. Forest Service, county Fish and Game Commission, a watershed conservation group called Trout Unlimited and a local land trust. The result is that every school is within a 10-minute walk of an open space for environmental education and all students get outdoor ecology lessons at least once a week.

“Every kid here lives in the mountains and we want them to learn the trails, the flora and fauna. We want them to have a strong sense of place,” he said. “Our goal is for kids to know the place they live, love it and take care of it no matter what they go on to do in life.”

Even though Plumas County is a politically conservative area compared to other parts of the state, with 58 percent supporting Donald Trump in the 2016 election, Wade has experienced very little pushback in his bid to expand the county’s environmental education curriculum — including the climate change components. Loving the outdoors, he said, is something everyone can agree on.

“Everyone who lives up here, no matter what their politics are, celebrates our shared love of this place,” he said. “We all love it up here — getting outside, the creeks, the forests, the meadows. Everyone’s been really supportive.”

Cowe, at Ten Strands, said she’s hopeful that every school in California can eventually have programs as ambitious as Plumas County’s and that all California children achieve what she described as “environmental literacy.”

“The scale we’d like to see this happen is enormous,” she said. “David Orr (environmental studies professor) once said ‘Hope is a verb with its sleeves rolled up.’ I feel that was about environmental education in California. The soil is prepared, now we need to roll up our sleeves.”

This story originally appeared on EdSource.org. EdSource is an independent journalism organization that works to engage Californians on key education challenges with the goal of enhancing learning success.